1.Technical Field
The disclosure relates in general to a flexible printed circuit board, and more particularly to a structure that uses an insulating layer to prevent the flexible printed circuit board from rupture.
2.Description of Related Art
Flat display modules have gained great popularity nowadays. Due to the features of slimness, low power consumption and low radiation, a liquid crystal display (LCD) has been widely used in portable electronic devices such as desktop computer, notebook computer, personal digital assistant (PDA), and mobile phone, and even gradually replaces cathode ray tube (CRT) monitor and conventional TV.
To satisfy the requirements of slimness and light weight expected of portable electronic products, manufacturers have to install various elements within limited internal space of the products. In general, the LCD panel is connected to external signals through a flexible printed circuit (FPC) board for controlling the frame of the display panel. Since the flexible printed circuit board has flexibility, the FPC can be folded backward to fit the internal space of the module and save the internal space of the LCD panel. Examples of flexible printed circuit boards known in the art can be found in U.S. Pat. No. 7,348,492 B1 and U.S. Patent Application Publication No. 2006/0109394 A1.
However, the currently used flexible printed circuit boards usually are a single-, double- or multi-layered structure. Since the flexible printed circuits of the electronic products need to be folded during assembly or use, the flexible printed circuit board with a thinner or weaker structure may easily be cut off by the glass edge of the LCD panel or ruptured due to the flecturing force. Under most circumstances, rupture may easily occur to the junction between the edges of the flexible printed circuit board and the glass substrate of the LCD panel or to the turning corners of the flexible printed circuit board. No matter rupture occurs to what position or in what manner, the operation of the overall LCD module will be severely affected, or may even incapacitate the normal operation of the LCD module.